/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.lvyh.lightframe.core.filter;

import com.lvyh.lightframe.core.invoke.request.RpcRequest;
import com.lvyh.lightframe.core.invoke.response.RpcResponse;
import com.lvyh.lightframe.common.exception.RpcRuntimeException;

/**
 * @author lvyh 2021/05/23.
 */
public abstract class AbstractFilter implements Filter {

    /**
     * Next node
     */
    protected AbstractFilter nextFilter = null;

    public void setNextFilter(AbstractFilter nextFilter) {
        this.nextFilter = nextFilter;
    }

    public final RpcResponse filter(RpcRequest request) {

        /** Execute current own method **/
        RpcResponse rpcResponse = doFilter(request);
        if (rpcResponse != null) {
            return rpcResponse;
        }

        /** Execute next node filter **/
        if (nextFilter != null && this != nextFilter) {
            rpcResponse = nextFilter.filter(request);
        }
        return rpcResponse;
    }

    /**
     * Filtering method for each node
     */
    public abstract RpcResponse doFilter(RpcRequest request) throws RpcRuntimeException;

}
